Iwate District, Iwate
By the middle Heian period, the kanji had changed to its present form, although it was also occasionally referred to as ‘Iwadenomori' (岩出の森郡) Iwate District was the northern frontier of Japan until the Enkyu-Emishi War of 1070, which extended the frontier to the northern coast of Honshu.
As with the rest of the region, the early history of Iwate District is uncertain.
Although Shiwa Castle was constructed in 803 as a major army base in the region, it fell into ruins only ten years later.
During the Muromachi period, the area gradually came under the control of the Nanbu clan from Nukanobu District to the north.
Following the Meiji restoration, Iwate District came under Rikuchū Province and became part of Morioka Prefecture in 1871.
colored area=original extent in Meiji period; green=present area (1=Shizukuishi, 2=Kuzumaki, 3=Iwate); blue=area transferred from Ninohe District; light green=area transferred from Kunohe District
Purple=present-day Morioka City (*. Morioka City from 1889 1. Yabukawa; 2. Tamayama; 3. Yonai; 4. Asagishi; 5. Yanagawa; 6. Nakano; 7. Motomiya; 8. Ōta; 14. Kuriyagawa; 23. Makibori: 24. Shibutami)
Blue=Takizawa City (then Takizawa Village)
Pink=Shizukuishi Town (9. Gosho; 10. Gomyōjin; 11. Nishiyama; 12. Shizukuishi)
Red=Hachimantai City (25. Ōbuke; 26. Dendō; 27. Matsuo; 28. Tairadate)
Orange=Iwate Town (21. Numakunai; 22. Kawaguchi; 29. Terada; 30. Ikkatai; 31. Midō)
Yellow=Kuzumaki Town (41. Kuzumaki; 42. Ekari)